Modern ICs have helped to integrate electronic circuitry to decrease size and cost. As a consequence, modern ICs can form complex circuitry and systems. For example, virtually all of the functionality of a system may be realized using one or a handful of ICs. Such circuitry and systems may receive and operate on both analog and digital signals, and may provide analog and digital signals.
The result has been a growing trend to produce circuitry and systems with increased numbers of transistors and similar devices. The increased number of devices has also coincided with increased power consumption of electronic circuits, such as ICs. Various mechanisms, such as device leakage, underlie the increased power consumption. Technologies such as metal oxide semiconductor (MOS) or complementary MOS (CMOS), which are used in a variety of IC devices, use devices such as transistors with leakage currents.
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